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Postglacial evolution of a small lake in the South Baltic coastal zone based on geochemical, pollen and subfossil Cladocera analysis

Niska M., Gadziszewska J., Jonczak J., Florek W., Kruczkowska B.

Oceanological and Hydrobiological Studies

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2018

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Vol. 47, No. 4

384--397

EN

The paper presents sedimentary records acquired as part of the research on the coastal cliff located between 221.3 and 221.4 km of the Slovincian (Słowinskie) Coast near Debina. Palynological and subfossil Cladocera analysis of sediments combined with geochemical data proves the existence of varying environmental conditions that occurred depending on the climate fluctuation. The Debina reservoir was formed in the Late Glacial period. Mud and gyttja were deposited in an initially cold proglacial lake. Species of Cladocera identified in this period indicate a deeper oligotrophic reservoir. The end of the Late Glacial cooling inhibited the development of fauna in the reservoir. Climate change at the beginning of the Holocene improved the habitat conditions in the Debina paleolake, which is reflected in the growth of zooplankton biodiversity and enrichment of the aquatic pollen content. We distinguished three phases that illustrate the evolution of the studied aquatic-mire ecosystem. In the following periods, the trophic level in the reservoir increased and significant water-level fluctuations led to periodic transformations of reservoirs into peat bogs. Gradually, the water-level lowering and the intensification of eolian processes led to terrestrialization of the paleolake.

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Late Pleistocene and Holocene environmental evolution of the Wkra River Valley near Bielawy Gołuskie (central Poland) recorded in palaeo-oxbow lake deposits

Niska M., Jonczak J., Gadziszewska J.

Geological Quarterly

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2017

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Vol. 61, No. 2

305--318

EN

This study aimed to reconstruct environmental changes in the Wkra River Valley near Bielawy Gołuskie (central Poland) based on geochemical, palynological and subfossil Cladocera analysis of deposits filling a palaeo-oxbow lake. Two sediment boreholes collected from the palaeochannel bend (BG-1) and neck (BG-2) include full sequences of organic deposits lying on clastic deposits. The lower part of the BG-1 borehole contains gyttja that accumulated during the Younger Dryas and the Preboreal, which is covered by reed peat of Preboreal and Boreal age. On top of this is alder peat that accumulated during the Atlantic. The ages of the gyttja and peat were confirmed by both radiocarbon dating and palynological analysis. The peats are characterized by a significant content of organic matter, which is relatively stable over time. This indicates a low intensity of mechanical denudation in the catchment, which is supported by low concentrations of aluminum and potassium. Calcium values greatly exceed these elements, suggesting that the lake was mainly fed by groundwater. Variation in trophic conditions over time is indicated by a vertical variability in the content of nitrogen, as well as by the Cladocera population. The strong decomposition of peat in the top layer of the mire, and increased concentrations of phosphorus and heavy metals, testify to increasing human activity during the most recent time periods.

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History of development and terrestrialization of Lake Starowlany in the Eemian Interglacial on the basis of Cladocera analysis (Sokółka Hills, NE Poland)

Niska M., Kołodziej A.

Studia Quaternaria

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2015

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Vol. 32, Nr 1

43--52

EN

This paper presents development of the paleolake Starowlany existing in the Eemian Interglacial (MIS 5e) in north-eastern Poland. The lake history is based on Cladocera analysis. The paleolake Starowlany is located in the central part of the Sokółka Hills, approximately 9 km north of the town of Sokółka in the North Podlasie Lowland. The sediments studied filled a southern part of a tunnel valley formed during the Warta Glaciation. The coring was carried out with a geological drilling and constituted a part of the framework aimed at preparing the Sokółka sheet for the Detailed Geological Map of Poland in scale 1:50 000. The core was 7 m long. Peaty silt, peats and organic silt were present at the depth of 4.0–6.6 m, under deluvial sands, tills and silt. Organic series was overlain by a clayey silt with no glacial cover. Cladocera analysis was conducted with 20 samples from a depth interval 6.6–4.1 m. Remains of 17 species of Cladocera were found, representing the families: Chydoridae, Sididae and Bosminidae. A vast majority of them were the littoral species. In the paleolake Starowlany four development zones were distinguished that reflected changes as regards temperature, trophic levels and changes of water level in the lake. The paleolake existed from the early until the middle Eemian. The highest water level and the most favorable conditions for zooplankton development occurred in zones SCZ I and II. The highest trophic level took place in SCZ III (middle Eemian). In the late Eemian the water level dropped and the paleolake was transformed into a wetland. At certain points, the higher water level enabled existence of a few Cladocera species. The reasons for disappearance of the paleolake Starowlany included a local decrease in groundwater levels as well as morphometric and geological characteristics of the lake.

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Development of the Kubłowo palaeolake, central Poland, during the Eemian Interglacial as against subfossil Cladocera analysis - preliminary results

Niska M., Roman M.

Studia Quaternaria

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2014

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Vol. 31, Nr 1

31--38

EN

The results of analysis of Cladocera occurrence in lacustrine sediments from the Kubłowo site have been presented. Lacustrine and peat deposits found there have been previously analyzed for pollen content (depth of 11.1-3.8 m) and represent a longest continuous Eemian-Vistulian succession in central Poland (Roman and Balwierz, 2010). Cladocera analysis was carried out on 25 samples from the depth of 9.20-10.5 m of an Eemian age section. The section consists of fine organic sand, silt with organic matter and gyttja. Identified were 19 species of subfossil Cladocera and five zones of fauna development were distinguished. In the early and mid-Eemian low frequency zooplankton in the palaeolake has been found. Best conditions for zooplankton development occurred in the late Eemian (R PAZ E6, E7). At the end of the Eemian a significant change of climate in a deterioration of environmental conditions and decreased presence of zooplankton has been noted. Cladocera results and the pollen data enable a reconstruction of the climatic and environmental changes in the Kubłowo palaeolake.

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Fossil Cladocera remains in the Eemian sediments - preservation, frequency and dominant species

Niska M.

Studia Quaternaria

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2012

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Vol. 29

31--43

EN

This paper presents the results of fossil Cladocera analysis using material obtained from seven palaeolakes of the Eemian interglacial located in Poland. The main aim of this study was to investigate the state of preservation and diversity of species in the Eemian Cladocera. The studied Eemian lakes were formed at the end of the Wartanian Glaciation in tunnel and kettle holes. They had preserved a continuous record of environmental changes throughout the Eemian interglacial, until the Vistulian Glaciation. Cladocera fossils found in Eemian sediments were thinner and had a more damaged structure than fossils from the Holocene. Low degree of fossil preservation forced to develop an alternative method for preparation of the fossils for the microscopic analysis. Cladocera species found in the examined palaeolakes corresponded to the present-day species inhabiting Poland and Central and Northern Europe. The changes in species composition resulting from climate changes corresponded to the current geographic distribution of Cladocera. Despite the poor condition of the obtained fossil remains, the results showed that cladoceran fossils in sedtments of palaeolakes may be used in the reconstruction of environmental conditions from the period preceding the last glaciation.

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Ewolucja środowiska w rynnie jeziora Jasień w obrazie palinologicznym i zmian fauny Cladocera

Miotk-Szpiganowicz G., Niska M.

Landform Analysis

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2008

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Vol. 7

102--112

PL

Na obszarze rynny jeziora Jasień zlokalizowano cztery stanowiska, dla których wykonano analizę palinologiczną i analizę szczątków Cladocera. Celem badań było odtworzenie przemian środowiska przyrodniczego na tym terenie. Rdzenie, z których pobrano próby do analiz, składały się głównie z osadów typu gytia i torf. Próbki do analiz wykonywano według standardowych procedur. Do obróbki danych liczbowych wykorzystywano program POLPAL. Otrzymane wyniki palinologiczne umożliwiły odtworzenie historii roślinności badanego terenu począwszy od okresu borealnego, a analiza szczątków Cladocera dostarczyła informacji o fazach rozwoju części zbiornika jeziornego Obrowo Duże.

EN

In order to reconstruct the environmental history of the Jasień Lake trough, pollen analysis and an analysis of Cladocera remains have been simultaneously carried out. Sediments for pollen research have been collected in the bay section of the Jasień Lake and in the Obrowo Małe peat bog. Cladocera remains have been sampled in two sites within a peat bog adjacent to the Obrowe Duże Lake. Preparation of samples for both analyses followed standard procedures. Numerical data have been elaborated using the POLPAL software. The results of the palynological study have allowed to decipher vegetation history since the Boreal period. The peat bog of Obrowo Małe began to form at the onset of the Atlantic period. Cladocera remains yielded information about phases of water body evolution in the part of the Obrowo Duże Lake, which subject to silting transformed into a low-level valley bog, and then into a transitional peat bog. Pollen and Cladocera analyses have been carried out on material collected at dissimilar sites, which practically excludes the possibility of correlation of results and allowed one only to reconstruct the major hydrological changes, common for the entire region. In the latest Holocene, in the Jasień Lake trough a trend towards water level decrease is observed due to both climatic and human impact. Further changes included the rise of trophic level in the lake and vegetation succession onto the shallower parts of the lake.

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Two climatic oscillations during the eemian interglacial : preliminary results of multi-proxy researches of palaeolake at solniki, Ne Poland

Kupryjanowicz M., Ciszek D., Morosław-Grabowska J., Marciniak B., Niska M.

Polish Geological Institute Special Papers

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2005

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Vol. 16

53--57

EN

Lake series from the Eemian Interglacial and Early Vistulian has been discovered at Solniki in the Białystok Upland region, north-eastern Poland. Preliminary results of interdisciplinary researches (pollen, diatom, Cladocera, isotopic and magnetic susceptibility analyses) were used to illustrate the changes of the Eemian climate. At present stage of investigations, there are found signs of two abrupt climatic oscillations - first with very humid climate took place at middle part of the regional Carpinus pollen zone (E5 R PAZ), and second with cold and dry climate at middle part of the regional Pinus zone (E7 R PAZ).

PL

W Solnikach na Wysoczyźnie Białostockiej (północno-wschodnia Polska) odkryto serię osadów jeziornych reprezentujących interglacjał eemski i wczesny vistulian. Wstępne wyniki badań interdyscyplinarnych (analiza pyłkowa, okrzemkowa i Cladocera, pomiary podatności magnetycznej osadów oraz zawartości izotopów stabilnych tlenu i węgla) wykorzystano do zilustrowania zmian klimatu podczas interglacjału eemskiego. Udokumentowano dwie gwałtowne oscylacje klimatu - pierwsza z ciepłym i bardzo wilgotnym klimatem (?opady) miała miejsce w środkowej części poziomu pyłkowego E5 Carpinus, druga z klimatem suchym i bardzo zimnym - w środkowej części poziomu E7 Pinus.

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Isotopic and Cladocera records of climate changes of Early Eemian at Besiekierz (Central Poland)

Mirosław-Grabowska J., Niska M.

Geological Quarterly

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2005

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Vol. 49, No. 1

67--74

EN

Results of stable isotope, Cladocera and pollen analyses of lacustrine sediments from Besiekierz (Central Poland) are presented. The Besiekierz palaeolake is located about 25 km north of Łódź (Central Poland) at 130 m a.s.l. The 4 m thick deposits comprise silty sands and clayey silts, overlain by calcareous gyttja and organic silts and peat. Pollen analysis documents that these deposits accumulated during the Eemian Interglacial and the Early Vistulian. Based on the results of stable isotope analyses, nine isotopic horizons (Is) were defined and characterized, and these enabled reconstruction of both climatic and hydrological changes. A positive trend in δ18O values and constant values of δ 13 suggest gradual climatic warming, while constant values of δ 18O and δ 13C indicate stable conditions and/or a fast rate of sedimentation. The fluctuation of isotopic values in the upper part of the succession probably points to a shallowing of the lake due to sedimentary infill. The subfossil cladoceran fauna in the Besiekierz succession is represented by 11 solely littoral species belonging to 3 families. Four zones of Cladocera development were distinguished. The Besiekierz palaeolake was a shallow reservoir. The initial period of its existence probably saw its greatest depth. The Cladocera species present indicate the initial oligotrophic status of the lake and its subsequent increase in trophic status.We compare the results of the isotopic, cladoceran and published palynological analyses, to distinguish and explain the phases of evolution of the lake.